1. Field of the Invention
This invention relates to a proportioning valve of a deceleration detecting type for a vehicle and more particularly to a proportioning valve which satisfactorily controls a braking force on rear wheels during a braking operation by detecting variation in the live load on the vehicle.
2. Description of the Prior Art
For braking a vehicle, it is often necessary to make the braking force on the rear wheels smaller than that on the front wheels. To meet this requirement, heretofore, a proportioning valve or a limiter valve has been inserted in a hydraulic brake passage from a master cylinder to each rear wheel cylinder.
Such a conventional control method, however, is hardly capable of covering the whole range of variation in the live load on a vehicle, particularly when the vehicle is a truck on which the live load varies to a great extent. Such incapability has caused an insufficient rear wheel braking force under a maximum live load condition and thus resulted in an increased braking distance. The present invention is directed to the solution of the problem of the conventional method.